1. Field of the Invention
The present invention relates to a pressure sensing system and method and, more particularly, pertains to a system for accurately sensing the pressure within a bag to which a pressure sensor is mounted.
2. Description of the Related Art
Vehicle inflatable restraint systems have proven to be dangerous to the occupants under certain circumstances--specifically if the occupant is of very light weight. There exists a need to detect the weight of the occupant so that the rate of inflation of the inflatable restraint can be modulated in proportion to the weight. Other methods have proven unsatisfactory from an accuracy, reliability, or cost standpoint. Some of these include costly strain gauge load cells or ultrasonic position sensors (assumes that the distance from the dash is proportional to weight). Other conventional methods require a pressure port and tube, which are sources for potential leakage.
Thus, there is a need for a system and method for accurately, reliably and affordably measuring the internal pressure of a liquid or air-filled bag positioned within a seat in a vehicle and for providing an indication of the weight of the occupant positioned over the seat.